Apparatus for producing fibers

ABSTRACT

In an apparatus for the production of continuous fibers from a fiberizable material, a bushing with a plurality of orifices supplies streams of fiberizable material which are attenuated in the form of continuous fibers. The fibers are collected on a spool spaced from the bushing. An induced draft zone between the bushing and the collection spool is provided for flowing air evenly across the fibers so that broken fibers are removed from the collection area.

United States atent 1191 Vaughan 1 Sept.'25, 1973 APPARATUS FOR PRODUCING FIBERS 3,304,163 2/1967 Holschlag 264/176 F 3,632,719 1/1972 Nozawa 264/176 F [75] Invemm- Raymnd vm'gham Buffalo 2,982,994 5/1961 Fernstrom 264/176 F [73] Assignee: The Carborundum Company,

Niagara Fall NY, Primary Examiner-George F. Mautz Assistant ExaminerEdward J. McCarthy [22] Flled' July 1971 Att0rneyDavid E. Dougherty et a1. [21] Appl. No.: 161,146

[57] ABSTRACT [52 us. Cl 425/72, 242/18 0, 242/54 R, In an apparatus for the Production of continuous fibers 425/436 from a fiberizable material, a bushing with a plurality 51 1m. (:1. B296 25/00, B65h 54/02 of orifices pp streams of fiberizable material [58] Field of Search 242/54 R, 18 G, 18 AA; which are attenuated in the form of continuous fibers. 57/555; 2 4/17 425/72 The fibers are collected on a spool spaced from the bushing. An induced draft zone between the bushing 5 References Cited and the collection spool is provided for flowing air UNITED STATES PATENTS evenly across the fibers so that broken fibers are re- 3 301 647 H1967 sh f r W X moved from the collection area.

a e 3,142,831 7/1964 Home 57/81 X 7 Claims, 4 Drawing Figures Pmmmsfl'z ms I 3.761.210

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OFNEY BACKGROUND OF THE INVENTION Continuous fibers are produced from a viscous material which is attenuated and solidifies in the form of continuous fibers. Generally, the fibers are drawn from streams flowing through orifices in a bushing. An attenuation unit and a collection unit (or a combined attenuation collection unit) are conveniently located a sufficient distance below the bushing to allow the filaments drawn from the streams of viscous fiberizable material to solidify into distinct uniform fibers.

The drawing operation is delicate in nature, especially when fine-diameter fibers are being produced. The fibers are under tension as they are drawn towards the attenuation unit, from the viscous streams at the bushing. Between the bushing and attenuation unit they are subject to breakage due to internal defects such as bubbles or dirt particles and external disturbances such as air currents, particles and droplets in the air, mechanical interference from the attenuation unit, and other fibers which have already broken.

When a drawing fiber breaks, the stream of fiberizable material continues to flow through the bushing orifice, but is no longer drawn off from below as a fiber. The material accumulates at the orifice until it has sufficient weight to fall as a droplet or bead. Such a bead will usually pull down a fiber behind it, but when the bead has stopped falling the fiber ceases to be pulled, and the fiberizable material again accumulates at the orifice. This intermittent reformation of beads will continue until the fiberizable material flowing through the orifice is drawn off continuously as a fiber.

A falling bead interferes with fiber production since it often comes in contact with and breaks several drawing fibers.

In addition, if a drawing fiber breaks at or near the attenuation unit, the fine filament which may be several feet in length will remain suspended from the bushing orifice during the time the head is forming. This length of fiber will float or drift around with the slightest air currents, which cannot be completely eliminated in a fiber drawing area. These drifting broken fibers will often come in contact with and break several drawing fibers. Therefore, it is desirable to remove broken fibers from the drawing area and to prevent the continual reformation of beads from an orifice where the fiber is broken. I

SUMMARY OF THE INVENTION In an apparatus for the production of continuous fibers from a fiberizable material, a bushing from which fibers are drawn supplies continuous streams of fiberizable material. lntermediate the bushing and a fiber drawing means there is provided a means for flowing air evenly across the fibers so that broken fibers are removed from the drawing fibers. Also, a collecting means is provided for drawing the broken fibers to prevent the reformation of beads.

The present invention obviates many of the deficiencies of prior art fiber producing apparatus by providing a controlled draft of clean air across the fibers so as to remove a broken fiber from the drawing area. As a result, fiber breakage is reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front elevational view of the apparatus of the present invention with portions shown in section;

FIG. 2 is a sectional view along line 2-2 of FIG. 1; and

FIG. 3 is a detailed view of the secondary spool.

FIG. 4 is a diagramatic view of the blower means DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT In more detail, a bushing 1 1 is supplied with a fiberizable material from a source 13. Material at the desired viscosity flows as streams from orifices, in the bushing 1 l. The orifices are formed in rows in the bottom of the trough-like bushing 11. The fiberizable material may be any material of suitable viscosity for forming fibers 15. The present invention is particularly suited for drawing fibers which have very little strength due to their thinness or composition.

The terms upper, lower, inner, outer and the like as hereinafter used are applied only for convenience of description and should not be taken as limiting the scope of this invention.

The fibers 15 are collected or gathered a sufficient distance below the bushing 11 to allow the fibers 15 to cool. A winder l7 draws and collects the fibers 15. The winder 17 is positioned below the bushing 11 and preferably offset thereto so that broken fibers and beads will not fall directly on the winder 17. In a zone which is intermediate the bushing 11 and winder 17, an induced unidirectional draft flows evenly across the fibers 15. This draft is generally horizontal and substantially perpendicular to the drawing fibers 15, and the direction of flow is such that it carries broken fibers and beads away from the offset winder 17. The draft is created between an inner wall 19 which faces the fibers l5 and an outer wall 21. The inner wall 19 lies in a plane substantially parallel to the plane formed by the plurality of fibers 15 and is spaced therefrom. The inner wall 19 which is porous or perforated may be made from a suitable air filter material so as to distribute the airflow evenly over the fibers 15. The inner wall 19 forms a chamber 25 with a solid rear wall 27 and side walls 29. An outlet 31 in the rear wall 27 is connected to the low pressure side of a fan or blower -'(50)for maintaining the chamber 25 under reduced pressure. The side of the inner wall 19 exterior to or facing away from the fibers 15 is under a reduced pres sure so as to create an induced draft through the inner wall 19. A steady flow of air (arrows) across the fibers overcomes tendencies for uncontrolled air flows and eddies.

The outer wall 21 which is spaced forward the fibers 15 extends longitudinally for substantially the length of the drawing fibers 15. Side walls 33 are formed between the outer wall 21 and the inner wall 19 so as to prevent disturbances exterior to the drawing apparatus from interfering with production. The side walls 33 are preferably transparent so that the fiber winding process may be easily observed. The lower end of the outer wall 21 is above the winder 17 permitting access to the winder 17. The outer wall 21 has perforations over the entire surface for creating an even air flow. The inner wall 19 and the outer wall 21 are preferably formed of matted filter media such as conventional furnace filters which are held in place by racks. The filter media serves to remove undesirable contaminants which might cause fiber breakage. The induced air flow tends to carry a broken fiber inwardly and away from the fibers being wound. In conventional apparatus, a broken fiber which is suspended in the drawing area is at the mercy of random air currents and it can rub or contact other fibers being wound and cause further fiber breakage. In accordance with the principles of the present invention, the steady flow of air transverse to the fibers causes a broken fiber to move inwardly away from the drawing fibers.

A means for gathering broken fibers and preventing bead reformation is provided between the fibers 15 being drawn and the inner wall 19. This includes secondary spool 35 located directly below the bushing 11 so that a bead tends to drop directly thereon and the fiber drawn behind the bead tends to wind therearound. The speed of the secondary spool 35 may be adjusted at a high enough speed to prevent the reformation of beads but at a low enough speed to keep the fibers 15 which are being collected thereupon from breaking and interfering again with the drawing fibers 15. Fiber winding may be restarted on the winder or primary spool 17 by removing the fiber from the secondary spool 35 by hand or other means and restarting the fiber on the primary spool 17.

The secondary winder or spool 35 which is shown in detail in FIG. 3 includes a pair of spaced sprockets 37 each mounted on a stub shaft 38. A plurality of slightly stretched springs 39 are connected between the sprockets 37 in a direction parallel to the alignment of the orifices in the bushing 11. A broken fiber contacting the spool 35 is wound thereon. Each sprocket 37 is connected to an endless chain 41 which passes inside and under the secondary spool 35. The chains 41 pass over one pair of sprockets 43 each mounted on a stub shaft 44 located forward of the secondary spool 35. The chains 41 then pass under another pair of sprockets 45 each mounted on a stub shaft 46 located beneath and behind the secondary spool 35. The chains 41 are vertically disposed and pass over a pair of drive sprockets 47 mounted on a drive shaft 48 spaced substantially below the bushing 11.

Disposed between the two chains 41 and connected thereto are a plurality of spaced bars 49. The bars 49 remove broken fibers which are drawn onto the inner wall 19 by the induced draft. As the rods 49 move downwardly and pass under the secondary spool 35,

spaced so as to form a conveyor which catches a broken fiber and contacts the fiber with the spool 35 to start a secondary winding. Horizontally connected between the chains 41 are the plurality of rods 49 which are spaced in the vertical direction. The conveyor system extends longitudinally in the path of air flow and directly behind the strands being wound. The secondary spool 35 is driven by the chains 41, which in turn are driven by the sprockets 47 on shaft 48. The drive shaft 48 is connected to a suitable drive means which is schematically illustrated in the drawings. The primary winder 17 is driven by suitable drive means also schematically illustrated.

While preferred embodiments of this invention have been described and illustrated, it is to be recognized that modifications and variations thereof may be made without departing from the spirit and scope of this invention as described in the appended claims.

What is claimed is:

1. An apparatus for producing continuous fibers comprising a bushing for supplying a plurality of streams of fiberizable material, means for drawing said material in the form of continuous fibers, said drawing means being spaced from said bushing, means separate from said drawing means for collecting broken fibers, said collecting means includes a spool for winding broken fibers, means for carrying broken fibers toward said collecting means, said carrying means including means for evenly flowing air in a direction transverse to the direction of movement of the drawing fibers.

2. An apparatus according to claim 1 wherein said air flow means includes a first wall on one side of said fbers, a second wall spaced from said first wall on the other side of said fibers, said first and second wall being porous to permit the flow of air therethrough, and means for creating a low pressure area adjacent said first wall.

3. Apparatus according to claim 2 wherein said means for creating a low pressure area comprises a chamber connected to said first wall, an outlet in said chamber, a blower means having the low pressure side connected to said outlet.

4. An apparatus according to claim 1 including a plurality of springs forming a peripheral surface of said spool.

5. An apparatus according to claim 1 including means moving continuously toward said spool for attaching broken fibers thereto.

6. An apparatus according to claim 5 wherein said attaching means comprises a conveyor assembly in the path of air flow.

7. An apparatus according to claim 6 wherein said conveyor assembly comprises av pair of endless chains, a plurality of rods horizontally disposed and vertically spaced between said chains. 

1. An apparatus for producing continuous fibers comprising a bushing for supplying a plurality of streams of fiberizable material, means for drawing said material in the form of continuous fibers, said drawing means being spaced from said bushing, means separate from said drawing means for collecting broken fibers, said collecting means includes a spool for winding broken fibers, means for carrying broken fibers toward said collecting means, said carrying means including means for evenly flowing air in a direction transverse to the direction of movement of the drawing fibers.
 2. An apparatus according to claim 1 wherein said air flow means includes a first wall on one side of said fibers, a second wall spaced from said first wall on the other side of said fibers, said first and second wall being porous to permit the flow of air therethrough, and means for creating a low pressure area adjacent said first wall.
 3. Apparatus according to claim 2 wherein said means for creating a low pressure area comprises a chamber connected to said first wall, an outlet in said chamber, a blower means having the low pressure side connected to said outlet.
 4. An apparatus according to claim 1 including a plurality of springs forming a peripheral surface of said spool.
 5. An apparatus according to claim 1 including means moving continuously toward said spool for attaching broken fibers thereto.
 6. An apparatus according to claim 5 wherein said attaching means comprises a conveyor assembly in the path of air flow.
 7. An apparatus according to claim 6 wherein said conveyor assembly comprises a pair of endless chains, a plurality of rods horizontally disposed and vertically spaced between said chains. 